code: def get_reduction_callable(cls, op):
      skipna = op.skipna
  
      def mean(x):
          return x.sum(skipna=skipna) / x.count()
  
      return mean
  
file_path: mars/mars/dataframe/reduction/mean.py
imports: from ...None import opcodes
  from ...config import options
  from ...core import OutputType
  from .core import DataFrameReductionOperand, DataFrameReductionMixin
label_desc: Use image node_id 1 for calling the DataFrameMean obj's underlying member method code with example usage: obj.get_reduction_callable(cls, op) and returns: mean, unknown